Gastrointestinal stromal tumor of other sites

This code signifies a malignant neoplasm arising from the interstitial cells of Cajal, or their precursors, located in an anatomical site within the gastrointestinal system not specifically classified elsewhere. These tumors are characterized by their origin in the GI tract's mesenchymal tissue, distinct from epithelial carcinomas.

Use this code when documentation specifies a gastrointestinal stromal tumor (GIST) located in an unspecified or "other" part of the GI tract, such as the omentum, mesentery, or retroperitoneum, that is not a primary site like the stomach, small intestine, or colon. Supporting documentation should clearly state the diagnosis of GIST and the specific "other" GI location.

• Do not use for GISTs of the stomach, small intestine, colon, or rectum; these have more specific codes.
• Ensure the pathology report confirms the diagnosis of GIST, as other mesenchymal tumors can occur in the GI tract.
• Sequence as the primary diagnosis when the GIST is the reason for the encounter, followed by codes for any associated symptoms or complications.